/Engine/Source/Runtime/MovieScene/Public/Evaluation/MovieSceneRootOverridePath.h
Find the first parent sequence ID that is common to both A and B
The leaf-most parent common to both paths, or MovieSceneSequenceID::Root
static [FMovieSceneSequenceID](API\Runtime\MovieScene\FMovieSceneSequenceID) FindCommonParent ( const [FSubSequencePath](API\Runtime\MovieScene\Evaluation\FSubSequencePath) & A, const [FSubSequencePath](API\Runtime\MovieScene\Evaluation\FSubSequencePath) & B )